Lapping a Plane Sole Flat, Advise Wanted

[Stew Denton]

Hi All, I am wanting to flatten the soles on a couple of my larger planes. I have a large granite stone, specifically made with an ultra flat surface I can use for my smaller planes, but it is too small for my bigger planes.

What is a good set up to do this with? I know David mentioned in another post that it is not difficult if you have the right set up.

Do you use special metal cutting sandpaper, etc., and if so what brand, product number, grit size, etc., do you use? What do you use to glue the stuff down, etc.

Also, it seems like a read a while back, while just a reader of the site, that one of they guys here is a machinist that will mill the sides and bottom flat, am I correct in this?

Any help will be appreciated.

Thanks and regards,

Stew

[David Weaver]

If you have a power tool surface that's absolutely flat in some dimension, that's good to use. If you have a bench that's very flat, then finding something supplemental to use on it is a good idea.

I have always used an 8x42x1/2 inch piece of glass on a flat bench surface. I use Mirka gold (doesn't matter the brand) aluminum oxide PSA stick down paper. PSA is important, as any paper that is not stuck down will dub the toe and tail of the plane in question. It won't render it unusable, but there's no reason for such ugliness, and the PSA paper can be used in push and pull directions.

That's pretty much it. Use the plane with the blade retracted and push the plane with the handles or with a hand between the handle and frog, as if you were using it. No wailing around is needed. If we are talking about a long jointer, sometimes it's easier to take a small block, say 2x3 and use 60 grit paper to do bulk removal of metal before final lapping, but I have also lapped #7s in a half hour or so on good fresh 80 grit al-ox paper/rolls.

Less is more lapping planes - get things as flat as they need to be and then stop.

[Derek Cohen]

I have a one metre length of granite (cheap offcut) to which I glue sandpaper ...

http://i13.photobucket.com/albums/a262/Derek50/Restoration/lapping1_zpsb971aa60.jpg

Edit to add:

1. Care must be taken to keep the sole of the plane very, very flat to the surface of the sandpaper. There is the constant danger that the plane will rock, and then this will round the sole, either/both along the length and width. Next push the plane forwards only; push forwards and down.

2. Sandpaper should be seen as a way of finishing - not starting - the lapping process. It can aid in finding high spots on the sole. These are - ideally - scraped away first. By the time one gets to sandpaper, the sole should be fairly flat.

Regards from Perth

Derek

[Jim Koepke]

Are you sure the sole of your planes needs lapping?

Is it end to end, side to side or a bit of both?

I use a hunk of granite that came from a monument maker for $25. It is as flat as can be checked with my straight edge.

293948

One thing is to be careful and constantly check what you are doing. The filings can collect and make your efforts go to making the sole worse. Especially be careful about not rounding the sole side to side.

jtk

[Tom Bussey]

I grind them.
293949 293950 293951 I grind them.

[Dave Parkis]

Tom Bussey from the post above is known as Tableasaw Tom and he will grind the sole flat and the sides perpendicular to the sole. His prices are reasonable and his work is excellent. I'm sure others will also recommend Tom.

[Mike Holbrook]

If you decide to do it yourself Highland Woodworking sells roles of 3M Stikit, PSA sandpaper in a couple different widths and a selection of grits. It holds reliably and it comes up off a metal or stone surface relatively easily too. You may be able to see a piece in the pictures I posted on my refurbishing planes thread in this forum. In my pictures the Stikit is stuck to my tablesaw table.

[Stew Denton]

Tom, I tried a couple of times to send you a private message, but obviously don't know what I am doing yet. I will try again tomorrow.

Also, thanks to all for the advise on this topic so far. Jim, you are right, I have not checked the planes I have, so need to check them for flatness and squareness. I just assumed that they were neither flat nor square.

Thanks and regards,

Stew

[Bob Jones]

Coarse sandpaper (initially), a good straightedge, a lot of patience, know where to apply pressure to selective remove high spots, know when to stop. Go from 80 grit to 600 grit. Alternative - Ignore all of this and ship them to Tom for grinding. Up to you.

[Steve Friedman]

Tom Bussey from the post above is known as Tableasaw Tom and he will grind the sole flat and the sides perpendicular to the sole. His prices are reasonable and his work is excellent. I'm sure others will also recommend Tom.
Absolutely. Unless you are bored and have nothing else to do, Tom's work is impeccable. I doubt that level of precision can be replicated by hand and his prices are extremely reasonable. He'll also do the sides if you plan to use it for shooting. He'll also do the frog.

As an added benefit, when you go to sell the plane, it will get a premium for having been in Tom's able hands.

Steve

[Mike Holbrook]

Flat or shinny?

So I decided to check out my Stanley 6C's bottom and sides for square/flatness. Using my engineers square the bottom was not showing any issues that my naked eye saw significant light through/under/around. I keep a piece of 3M Stickit on my tablesaw table (it's main use now). I ran the plane bottoms and sides over it a few times. I could see a few gradual, small high spots and so I spent a little while lapping, particularly the bottom. I have a LV BU Jack & Smoother if I want to shoot something. Checking the 6C's bottom now I am having a very hard time seeing anything significantly out of square. The bottom is not shinny all over like it would be if I worked down to a low grit making sure the whole bottom was dead flat. I think for my purposes I will not see any difference in workpieces if I go further with flattening the bottom.

My question is whether or not I now have, for practical purposes, a flat bottom? It seems to me that further work would fall into the realm of beauty treatment rather than practical improvement of the functional ability of the tool to do the work. Is there any reason to proceed further with the flattening process that I may not be aware of?

[David Weaver]

I'd stop where you are now and use the plane. If you don't notice any issues while using it, then there are none.

[Jim Matthews]

I use a hunk of granite that came from a monument maker for $25. It is as flat as can be checked with my straight edge.

293948


jtk

Ahh - the infamous photo that started it all...

My wife called this Arnold Schwarzenegger's sawhorse, because only weightlifters could move it.

[Jim Matthews]

If you don't notice any issues while using it, then there are none.

If Star Wars had been a Home Repair show, Yoda would have said this.

[Curt Putnam]

If the plane takes shavings that you want, it ain't broke and don't fix it.
If it is broke (not flat - not square - does not take good shavings) send it to Tablesaw Tom (Bussey). Unless you have a lot of skill and experience, lapping a big plane should be left to the pro. I have several planes that he has ground and they are superb.

[David Weaver]

Squaring a plane is a job for a pro. Paying someone to grind a plane that only needs a flat sole is a waste of money. (not trying to be rude, just stating - it's easier to get a plane beyond functionally flat for woodworking than it is to do any number of actual woodworking things. Getting one square without scraping - if it has metal sides, can be another story, but we have to be a bit realistic about how many dead square planes we need to have, and how many things we're actually going to need to shoot -especially if most of our board ends are tenons or end up flush with another surface to be trimmed and planed later and then covered with mouldings).

[Jim Koepke]

I'd stop where you are now and use the plane.

From what you said,
Using my engineers square the bottom was not showing any issues that my naked eye
I would not have bothered with the lapping in the first place.

jtk

[Mike Holbrook]

Thanks for the answers guys. I think this is an important part of the OP's question. I ran the plane over sand paper when I thought it was perfectly serviceable because I was curious to see if and how much it might still be out of flat. I was also curious how much effort might be involved in getting it as flat and evenly buffed as I could. I was curious for two reasons.

1) I wanted to have an idea how much work it would take to take the bottom from functionally "flat" to as close as I could get it to "perfectly" flat and buffed nice and shinny. My conclusion was that the remaining work required to make the bottom "perfectly" flat and buffed was quite substantial using the methods, tools and supplies I have. I concluded, as I think David implies above that there were many things more deserving of my time. I think if I wanted a "perfectly" square and flat vintage plane I would send it off to get the work done. Someone like Tablesaw Tom obviously has better tools and skills that will produce more accurate results, allowing me to get back to projects. I just happen to have several LV planes and a collection of easier to adjust wood planes that I feel can handle any chores requiring that level of refinement in terms of plane bottom & side flatness & squareness.

2) I was interested in seeing what PSA sand paper on my steel tablesaw table might "bring to light" vs my naked eye and a good engineers square. I was interested, as I use this method to flatten and square wood plane bodies. I found that this method of flattening and squaring is capable of accuracy beyond what I can actually see using a good square and my naked eye. I feel reassured that the methods I am using to flatten and square my wood planes are at least as accurate as I need for them to be.

I believe I find corroboration from fellow woodworkers above who's opinion I have reason to respect.

[David Weaver]

I can't say anything about your tablesaw, but a delta hybrid that I had was a hundredth hollow in the length, but good going across its width as long as the tables were installed properly.

My glass was a piece of "glass shelf" (the cheapest way to get a large piece like that) that a glass shop had on hand for people who break glass cabinet shelves.

It was $20, and already dead flat. It's thick enough that a low profile dog holds it in place. According to a starrett 380, it is far far flatter on the top of my bench than my TS was.

All of that said, the use test is still the determinant of the amount of work to be done. I do, despite liking to lap the bottom of my planes, have some planes that I use that have never been lapped, and have also seen planes that I would consider unusable without lapping - like metal jointers with a concave sole - one where you can't plane a sprung joint.

[Mike Holbrook]

My tablesaw is a General International with a table extension that I believe was manufactured to acceptable tolerances. I am happy with this 27" wide surface but might find use for an even larger more versatile surface. I have not used my tablesaw for much, other than flattening, for some time and I am thinking about getting rid of it to make space for other tools/work surfaces.

I have an old metal table/desk that belonged to my grandfather. I am in the process of restoring this table/desk. I am making a new top for it and I am considering making a portion or all of that top out of one of the composite stones used for counter tops. I understand these surfaces are manufactured to high standards, similar to glass. Such a hard, very flat, water proof, heat proof, stain resistant surface might be useful for several jobs in my workshop.

[Stew Denton]

I received a nice note from Tom, and he advised that I may not even need to flatten what I have. He did recommend that I wax them up and see how well they can do first, so I guess for now I am going to stand pat, and when I am able will take his advise.

I had surgery a little over a month ago, am doing well and improving every week, and have even gone back to work. However, I do not do anything very physical yet, and mostly rest after I get home. That said, I am working on restoring a couple of small saws that my grandsons are eventually going to grow into and use when they come to visit us, but that is not very physical. Thus, at this point I am not going to be doing any serious planning for at least a couple more weeks or so.


In his note, Tom advised that he had answered some of my questions, but also advised that it would probably raise other questions in my mind, and he was right, I now have more questions, which I will probably ask as a separate thread on the board.

Thank you for all of the advise, it is very much appreciated.

Thanks and regards,

Stew

[Ray Bohn]

Tom Bussey from the post above is known as Tableasaw Tom and he will grind the sole flat and the sides perpendicular to the sole. His prices are reasonable and his work is excellent. I'm sure others will also recommend Tom.

+1
There are some people that will swear that a flat sole is not needed. I found that the three planes Tom worked on for me all perform substantially better than before his magic touch.